Prince Charles and Camilla in mid-air terror

A helicopter carrying Prince Charles and the Duchess of Cornwall was forced to make an emergency landing, leaving Camilla terrified, it emerged on Wednesday.

The mid-air incident was caused after a tiny metal ball in the aircraft’s control system broke, leaving its two pilots unable to fly in a straight line.

The royal couple were being flown from London to the Hay-on-Wye Literary Festival in Wales when their Sikorsky S-76C suddenly began to yaw - the word pilots use to describe a change in direction.

With neither pilot able to balance the aircraft properly, its 53-year-old captain was forced to declare a “pan emergency” - one level of danger below a mayday call - and attempt to land at a nearby airfield.

A royal aide described the incident as “pretty hairy” and sources close to Camilla, who is a nervous flyer at the best of times, told the Mail she was extremely frightened. One said the sudden loss of control forced the pilots to land immediately, adding: “It was genuinely terrifying.”

“The helicopter veered and there was apparently nothing they could do about it.

“It was a heart-in-mouth moment. The Duchess was very, very shaken.”

The helicopter, manufactured in 2009, was carrying the royal couple and four others, including their bodyguards, as well as the two-man crew during the incident last May.

It began to yaw to the right as it approached Denham aerodrome in Buckinghamshire.

The pilots immediately realised the helicopter was in trouble and, after performing a quick systems check, declared an emergency and briefed their royal passengers. They then carried out a successful emergency “running landing”, in which a helicopter is brought in at a shallow angle and skids to a halt instead of descending from a hover.

Charles and Camilla insisted on continuing their journey by car, arriving three hours late and, apparently, with smiles on their faces.

Neither alluded to the drama during the engagement and were reported look relaxed. Aides said they were determined not to let members of the public at the festival down.

“They were unflappable despite what they went through. If anyone else had gone through what they did they would have cancelled their day,” said one well-wisher.

An investigation by the Air Accidents Investigation Branch (AAIB) into the episode, which was made public for the first time yesterday, said it was caused when the 2mm ball shattered, leading to a leak of hydraulic pressure that restricted steering. - Daily Mail